Want to understand Texas’ water crisis? Start with the guide to water terms.

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This article is part of Running Out, an occasional series about Texas’ water crisis. Read more stories about the threats facing Texas’ water supply here.

Texas legislative leaders have prioritized securing the state’s long-term water supply this year.

The state is losing billions of gallons of water annually to poor infrastructure. Warmer weather is depleting the state’s reservoirs and rivers. And the state’s rapid growth — and increased energy demands — is adding considerable pressure.

While the debate over solutions is just getting started at the Legislature, the most likely outcome will include asking voters to approve more money for water projects. That means you’ll hear a lot about water between now and the November election.

Water is complicated, and so is its language. To better understand Texas’ water landscape, the Texas Tribune created the glossary below.

Water sources

Groundwater — Water that exists underground in soil, sand and rock. Groundwater is created by precipitation, including rain and melting snow and ice that seeps into the ground.

Aquifers — A body of rock or sediment underground that holds groundwater. Aquifers can be formed through many types of sediments, including gravel, sandstone, and fractured limestone. In Texas, there are nine major aquifers and 22 minor aquifers that store groundwater. Private landowners and cities access this water using wells.

Recharge — An increase in the amount of water that enters an aquifer. This can occur naturally, through precipitation that seeps into the soil and moves down where water is stored. Or it can come from human-controlled methods, like redirecting water across the surface through basins or ponds, or injecting water directly through injection wells.

Surface water — Any source of water that is found above ground, on the Earth’s surface. This includes saltwater in the ocean, and freshwater in rivers, streams and lakes. Surface water supplies in Texas come from 15 major river basins, eight coastal basins and more than 180 reservoirs.

Water table — An underground boundary that separates the soil surface and the area where groundwater is being stored.

Water management

Reservoirs — Man-made lakes that serve as big pools to hold drinking water. Most reservoirs are created by constructing dams across rivers or lakes to control water levels. The dam and gates control the amount of water that flows out of the reservoir. Reservoirs are built to hold back a certain amount of water because water levels in a river can vary over time. There are different types of reservoirs; the most common are for flood control and water conservation. Texas has 188 reservoirs that supply water to people.

Dam — A barrier that stops or controls the flow of surface water. Modern-day dams are often made of concrete, though they can also be made of steel or PVC.

Drought — An extended period with less than average rain, snow or ice, which impacts water levels at aquifers and reservoirs. A lack of water leads local officials to place restrictions on people’s water usage and limits agricultural production. Texas water planners use the 1950 drought as a benchmark for statewide water planning.

Acre-foot — An acre-foot of water is enough to cover approximately the size of a football field to a depth of one foot. One acre-foot of water is equal to almost 326,000 gallons — enough water to last six Texans for one year.

Cubic feet per second (cfs) — The rate at which water passes a specific point over a period of time. It's often used to report the flow of streams. One cfs is equal to about 450 gallons per minute.

Irrigation — The application of water to crops through pipes, canals, sprinklers or drip streams.

Water reuse — The process of reclaiming water from a variety of sources to treat and recycle for other purposes.

Water infrastructure — Man-made systems for meeting water and wastewater needs, such as dams, wells, conveyance systems, water pipes and water treatment plants.

Governance

Water utility — A public or private entity that provides water directly to residents and businesses. For the majority of the utilities, an acronym is listed after the name describing the type of utility. Examples: Municipal Water Authority, Municipal Utility District, Water District and Water System.

Rule of capture — The law that essentially means the first person to extract groundwater is the rightful owner of that source of water. Landowners own the water beneath them and reserve the right to pump as much water as they need. Texas governs groundwater by this rule.

Groundwater conservation districts — A local or regional governing body tasked with developing and implementing management plans to conserve and protect groundwater resources. Districts try to maintain a balance between protecting property rights and protecting the water resource.

Texas Water Development Board — The state agency created after an intense drought in 1950. It serves as a bank that funds water projects across the state to fix leaking pipes, flood mitigation projects and water research.

Texas Water Caucus — A bipartisan group of lawmakers that focuses on prioritizing the state’s water resources at the Capitol. The caucus was established during the 2023 legislative session. It includes 74 members from the House of Representatives and one Senate member.

Texas Commission on Environmental Quality — A state agency that regulates air, water and waste management. This agency issues permits to businesses and people for surface water.

Boil-water notice — An alert that indicates when water in a distribution system may be unsafe for consumption. The Texas Commission on Environmental Quality, the state’s environmental agency, requires that residents of the affected area boil water to help destroy harmful bacteria when they want to use it for drinking and cooking. TCEQ is also the agency that must lift the notice.

Texas Water Fund — A one-time investment of $1 billion created in the 2023 legislative session using surplus state funds that funded water infrastructure projects.

Texas water plan — A guide the state uses to manage the long-term demand for the state’s water resources. The plan accounts for the water needs for municipal, irrigation, and livestock, among other uses. It also addresses each region in Texas and proposes water supply solutions to meet demand. It is written by the Texas Water Development Board, and the final plan is submitted to the Texas Legislature, governor and lieutenant governor.

Other types of water and treatments

Desalination — The process of removing salt from seawater or salty groundwater so it can be used for drinking water, irrigation and industrial uses. Researchers say desalination could be a solution to water shortages.

Produced water — Water that comes out of the ground as wastewater during the extraction of oil and gas production.

Brackish water — Salty groundwater with salinity levels higher than fresh water, but lower than sea water. Brackish groundwater forms when fresh and sea water mix or rainfall seeps into the ground and mixes with minerals within the subsurface.

Water runoff — When there is more water than the land can absorb, causing erosion, flooding, and water pollution.

Sources:

• https://www.twdb.texas.gov/publications/state_water_plan/2012/12.pd
• https://www.twdb.texas.gov/conservation/education/doc/acre-foot_flyer.pdf
• https://centraltexaswatercoalition.org/wp-content/uploads/Water-101-Definitions-from-LCRA.pdf
• https://www.texastribune.org/2024/05/03/weather-flooding-polk-liberty-montgomery-harris-county/
• https://texaslivingwaters.org/state-and-regional-water-plan/#:~:text=The%20Texas%20State%20Water%20Plan,solutions%20to%20meet%20those%20demands.

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